The early empires of Mesopotamia
The broad plain through which the Tigris and EUphrates river flow gave birth to the world's first cities. Irrigation systems made it possible to support substantial populations and complex adminsitrative structures. With urbanization came more developed economies and trade, while competition between cities led to warfare and the first empires. The earliest cities appeared in Mesopotamia in the second half of the 4th millennium BC: at Uruk, Ur, Tell 'Uqair and Susa vast and elaborately decorated ceremonial complexes were built at the centres of urban settlements, probably under the leadership of families eager to display their power and their respect for the gods. The fertile plains and valleys watered by the Tigris and the Euphrates produced food surpluses sufficient to support these elaborate new centres and their complex social structures. The cities were the basic political units of Mesopotamia. Religion was fundamental to their social organization: the rulers of cities presented themselves as favoured servants of the gods, while lower down the social scale aricultural workers had a necessary role in producing the materials for the sacrifices and offerings to the gods. The ciites established diplomatic and trade relationships with each other, although little is known of the mechanisms for this. Finds of goods from Uruk, the predominant city in Mesopotamia from around 3500 BC have come from as far afield as Susa and Syria. The effect of trade and gift-exchange between cities encouraged the development of a common culture from the edges of the Persian Gulf to Mari in the northwest and Ashur in the north. Although other languages were spoken, the early use of Sumerian as a written language has led to the use of the term "Sumerian" to describe the culture and social of the early and middle 3rd millennium. The Empire of Agade Towards the end of the 3rd millennium powerful leaders attempted to expand their influence over a wider area. The first was Sargon (c''.2296-2240 BC), who created a new political centre at Agade, also known as Akkad, before conquering the cities of southern Mesopotamia and claiming authority over areas as far west as Byblos. The empire of Agade was enlarged by Sargon's Naram-Sin (2213-2176 BC), but within a generation of his death it had disappeared, as its subject cities reasserted their independence. The rise of Agade had long-lasting effects on the region, with Akkadian (whose variants included Babylonian and Assyrian) replacing Sumerian as the main language of Mesopotamia. A century later the rulers of the Third Dynasty of Ur (Ur III: 2047-1090 BC), beginning with Ur-Nammu, built an empire in southern Mesopotamia, but in common with the other early Mesopotamian empires it was not long-lasting and its decline left a number of important cities competing for power. The centre of activity moved to northern Mesopotamia, and a new ellite emerge - the Amorites - who had previously been excluded from power. The most successful Amorite leader was Shamshi-Adad I, who established a short-lived empire in Assyria in the years after 1750 BC. After his death the region returned to a period of competing rulers, as reflected by the assessment of an advisor to Zimri-Lim or Mari (''c. 1714-1700 BC): "There is no king who is strong by himself: 10 or 15 kings follow Hammurabi of Babylon, as many follow Rim-Sin of Larsa, Ibalpiel of Eshnunna and Amutpiel of Qatna, while 20 kings follow Yarim-Lim of Yamkhad." Soon after this Hammurabi was able to establish an empire of hiw own, and Babylon became a leading power in the region for the first time. The law code of Hammurabi Hammurabi is most famous for his law code, inscribed on a large stone with a carving of the king in the present of Shamash, the Babylonian sun-god. Although it is presented as a practical collection of laws including the principle of punishment with "an eye for an eye", the primary function of the document was probably to advertise the achievements of Hammurabi's reign. After his death, his successors in the First Dynasty of Babylon ruled for about 90 years before the city was raided by the Hittites, and a new phase in the history of Mesopotamia began.